1. Field of the Invention
The invention relates to a light-emitting device, and more particularly relates to a light-emitting device capable of improving the light-emitting efficiency.
2. Description of Related Art
In general, a light-emitting diode wafer usually is fabricated by following steps: providing a substrate, forming an epitaxial structure on the substrate by epitaxial growth, and then disposing electrodes on the epitaxial structure to provide electric power, so that the light-emitting diode wafer may emit light by photoelectric effect. Thereafter, a plurality of scribe lines crisscrossing to each other is formed on the epitaxial structure by photolithography technique. Further, two adjacent scribe lines in vertical direction and two adjacent scribe lines in horizontal direction collectively define a light-emitting diode die. Thereafter, back-end processes (polishing and dicing) are performed to divide the light-emitting diode wafer into a plurality of light-emitting diode dices, thereby finishing the fabrication of a light-emitting diode.
Since sidewalls of the light-emitting diode obtained by applying conventional dicing technique are in planar shape, and there is a difference between the refractive index of the material of the light-emitting diode and the refractive index of air, most of light emitted at the side surfaces of the light-emitting diode would be totally reflected, and only a small portion of light emitted from the light-emitting diode can pass through the side surfaces of the light-emitting diode. Consequently, the light emitted at the side surfaces of the light-emitting diode cannot be effectively utilized, thereby affecting the light emitting efficiency at the side surfaces of the light-emitting diode and reducing the light-emitting brightness of the light-emitting diode. Therefore, improving the light-emitting amount at the side surfaces of the light-emitting diode to enhance the overall light-emitting efficiency has to be resolved.